A life-size sex doll lives in a modest apartment in Tokyo, she can't speak nor move and she's the only companion of his master, a man of middle age. He speaks to her, bathes and then make love every day when he returns from work.

The daily routine is broken when fantasy becomes reality. All of a sudden she comes to life and realizes she has a heart. She's unable to comprehendwhat is around her, however she knows there is a world waiting to be explored beyond the walls of the small floor and her selfish master. Eventually she dares to go outside world and meets people of all kinds, but no one is able to explain her what it means "to be alive".